Process of producing a carbonated hop-malt beverage

ABSTRACT

In a process of producing a carbonated hop-malt beverage in which a wort concentrate is produced from malt extract, hop concentrate and yeast by a heat treatment, fermentation, filtration and pasteurization, the wort concentrate is packaged for a long shelf life and for the consumption of the beverage is diluted with water and carbon dioxide, it is desired to produce a beverage which in its taste and consistency and particularly as regards frothing is similar to conventional beer. This is accomplished in that in the preparation of the wort concentrate from dilute malt extract, protein is separated by being heated and precipitated and hop concentrate and yeast are added to the resulting liquor, which is subsequently fermented. After an optional addition of nutrients and aromas to the liquor the fermentation is interrupted by shock cooling. The substrate is filtered, pasteurized and packaged. 
     To produce the potable beverage that wort concentrate may be supplied at a controlled rate to a mixing stage, in which the wort concentrate is continuously diluted with CO 2  -containing water and can finally be dispensed under superatmospheric pressure.

This invention relates to a process of producing a carbonated hop-maltbeverage, in which a wort concentrate is produced from malt extract, hopconcentrate and yeast by a heat treatment, fermentation, filtration andpasteurization. The wort concentrate is packaged for a long shelf lifeand is diluted with water and carbon dioxide for consumption.

The resultant beverage may be dispensed from a dispenser adapted to mixwater, CO₂ and the concentrate in adjustable proportions.

For a long time there has been desire for a hop-malt beverage which isequal or similar in taste to the conventional kinds of beer but isnon-alcoholic or at least has a very low alcohol content. Such abeverage also should be substantially similar or identical toconventional kinds of beer as regards frothing and consistency of froth.The use of a concentrate, to which water and carbon dioxide are addedonly before the beverage is consumed, decreases the volume and weight tobe transported.

It has repeatedly been proposed first to produce a substantiallyfinished, normal beer, then to expel the carbon dioxide (CO₂) and toseparate the alcohol by fractional distillation, and to thicken theresidue so as to obtain a concentrate, from which a potable beverage isproduced by admixing it to carbonated water. The taste, consistency andfrothing are not satisfactory. Specifically, the thickening anddistillation result in a decisive change of the taste from the typicaltaste of beer. At best, a thickening and a subsequent dilution in aratio of 1:4 are possible.

Published German Application No. 1,417,566 discloses a process ofproducing non-alcoholic malt-containing foodstuffs in which a maltosesolution is boiled in the presence of a substance which contains tannicacid, such as hops, so that the dregs are separated by flocculation andfiltration, and that boiled maltose solution is permitted to cool and issubsequently contacted with brewer's yeast for a short time and issubsequently centrifuged or filtered. In that case the brewer's yeast isused mainly as an agent for assisting the separation of the undesiredsubstances and is prevented by refrigeration from breaking down themaltose. After that treatment the maltose solution is thickened to forma powder or sirup and may then be used as a baking aid or foodstuff aswell as for the preparation of non-alcoholic beverages. For the latterpurpose the thickened product is diluted with carbonated water. Whereasa taste like that of malt beer can be achieved, the beverage differsfrom conventional kinds of beer as regards frothing and actual taste.The thickened product is highly hygroscopic and is protected by anadmixture of carbon dioxide before it is transported.

Low-alcohol beers or hop-malt beverages can also be made in accordancewith special recipes, like conventional kinds of beer, in that thefermentation is interrupted soon so that alcohol is produced only insmall quantities. Such beers differ in taste from other kinds of beerand it is virtually impossible to process them so as to form aconcentrate.

Dispensers for the preparation of non-alcoholic beverages are known,e.g., from Published German Applications Nos. 28 55 839, 30 46 545, 3213 580 and 34 17 005, wherein a concentrate is supplied undersubstantially normal pressure through a metering nozzle or an outletpipe to a mixing vessel, which is fed in a corresponding proportionwhich CO₂ -containing, i.e., carbonated water so that the concentrateand carbonated water mix to form a beverage, which can be dischargedfrom the tap under normal pressure. It is also known to accommodate thesupply tank for the concentrate and the carbonizer in an icebox oranother refrigerator. In that case there is no strong frothing, as isencountered in the dilution of a wort concentrate. If beer and beerlikebeverages were dispensed under normal pressure, the wort concentratewould not be sufficiently dissolved and the correct proportioning ofwort concentrate and carbonated water would not be ensured. Other knowndispensers, in which a flavor concentrate, such as a fruit juice, ispressurized, are also unsuitable for dispensing hop-malt beverages ofthe kind mentioned first hereinbefore. Such dispensers comprise CO₂supply tanks and ports for connection to a water line and are adapted tobe coupled to pressure-resisting tanks for a flavor concentrate, such asfruit juice. The CO₂ line leads to that tank. In that case the CO₂ isused to expel the concentrate from the pressure-resisting tank and theCO₂ -concentrate mixture is introduced through an injector into a linein which the water is conducted so that the components of the beverageare mixed in controlled proportions and the finished beverage can bedispensed under superatmospheric pressure at the tap. In connection withhop-malt beverages of the kind stated the expulsion of the wortconcentrate by means of CO₂ might give rise to extreme frothingresulting in a malfunction of the entire dispenser.

It is an object of the invention to provide a process for the productionof a wort concentrate and of a potable hop-malt beverage with the aid ofmeans which are simpler than those used before and in such a manner thatthe finished beverage has a taste similar to that of conventional beerscan form a froth like that of beer.

The main object set forth is accomplished in according to the inventionwith a process of producing a wort concentrate having a long shelf life,which comprises the steps of diluting a malt extract containing proteinto 30 to 40 Brix, heating the diluted malt extract above the coagulationtemperature of protein until the protein has been coagulated, adding aprecipitant for the protein, removing the precipitated protein and theprecipitant to purify the malt extract, adding hop concentrate and yeastto the purified malt extract to obtain a clear liquor, and fermentingthe clear liquor at a temperature of 28° C. and 32° C. to obtain a wortconcentrate having an alcohol content not exceeding about 2.5%, byvolume. A carbonated hop-malt beverage is produced from this wortconcentrate by diluting the wort concentrate at a controlled rate withCO₂ -containing water to obtain the hop-malt beverage.

The process in accordance with the invention for the preparation of thewort concentrate differs conceptually from the process steps carried outin the conventional production of beer. In the conventional productionof beer the dregs, particularly the proteins, are not separated beforethe fermentation and a useful beverage or a precursor of a beverage isnot provided before that separation.

Owing to the recognition that particularly in conjunction withrelatively high concentrations of maltose a prolonged fermentation willnecessarily result in a high alcohol content, a purification of the maltconcentrate to remove protein is performed in the process in accordancewith the invention so that a fermentation is not required for thatpurification. The fermentation which is effected is not intended totransform alcohol but to break down the excess maltose and, at the sametime, to generate in the malt concentrate the typical taste of beerwithout artificial aromas. The fermentation is performed at a highmaltose concentration, a high hop content and a constant temperature.For instance, a malt extract is used which has been diluted to valuesbetween 30 and 40 Brix (% by volume), particularly 35 Brix, and thefermentation temperature is about 30° C. The fermentation is effectedonly for about 24 hours or until an alcohol content not in excess of2.5% by volume has been reached and is then interrupted by shockchilling. The wort concentrate which has been produced under suchconditions can be diluted at a ratio from 1:9 to 1:10. Even if the lowalcohol content is not expelled during the pasteurization, the finishedbeverage will have only a negligibly low alcohol content.

After the pasteurization the substrate may be conducted in a stream tothe filing station and additional aromas, particularly hop aromas, maybe injected during that step in order to obtain certain flavors.

In the preparation of the wort concentrate, a high concentration isachieved and the concentrate will not become cloudy and will preserve astable aroma structure and will not change its taste even duringprolonged storage. It can be diluted so as to form a beerlike frothstructure. In that connection an important process step resides in thatthe concentrate is diluted by an admixing of carbonated water,particularly in a continuous operation, rather than in that theconcentrate is injected into the water by means of CO₂ as in theconventional vending machines for fruit beverages and the like.

A dispenser for the potable beverage is adapted to mix water, CO₂ andthe wort concentrate in adjustable proportions so that the finishedbeverage is dispensed from an outlet, and comprises a cooled carbonizerfor producing carbonated water from water and CO₂, a mixer connected tothe carbonizer, a metering device connecting the mixer to a sterilecoupling port, and packages containing the wort concentrate and adaptedto be connected under sterile conditions to the coupling port. The mixerhas an outlet which communicates through a cooling stage with a tap. Themetering device may consist of a diaphragm pump which has an actuatingline extending in the CO₂ gas stream supplied to the carbonizer. Asimple and exact apparatus will be obtained if carbonated water and wortconcentrate can be mixed in the correct proportions undersuperatmospheric pressure in the dispenser and can be dispensed undersuperatmospheric pressure. An aftercooling and stilling may be effectedafter the mixing region.

The subject matter of the invention is illustrated by way of example inthe drawing. FIG. 1 is a block diagram illustrating the process ofpreparing the wort concentrate. FIG. 2 is a block diagram of adispenser.

Liquid, light-colored, tart malt extract, which has been diluted, e.g.,to 35 Brix and has been supplied to a container 1 as indicated by thearrow 2, is heated to 75° C. in a process stage 1, in which aprecipitant has been added (arrow 3). The precipitant effects aprecipitation of the protein, which coagulates as it is heated and issubsequently removed together with the precipitant, which may consist ofcalcined alumina (arrow 4).

The thus prepurified malt extract is left for a predetermined period oftime in a decanting stage 5. The resulting sump consisting of dregs isremoved (arrow 6) so that a malt-containing clear liquor is left. In aprocess stage 7, hop concentrate (arrow 8) is added to that liquor. Aspecial yeast (brewer's yeast, arrow 10) is added in a process stage 9.

After the addition of hops and yeast to the clear liquor, the latter isfermented in a process stage 11 at a controlled temperature of, e.g.,30° C. for a selected time of, e.g., 24 hours or until a predeterminedalcohol content of, e.g., 2.5% by volume has been reached. The excessivemaltose is broken down at the same time. Additional nutrients or aromas,hop concentrate and the like are added in a process stage 12 (arrow 13).In a succeeding process stage 14 the fermentation is interrupted by ashock cooling to the freezing point. The resulting wort is filtered overkieselguhr in a process stage 15 so that a clear wort becomes availablein a stage 16. That clear wort is then caused to flow through a stage17, in which it is pasteurized by being heated to 95° C., close to itsboiling point, for 30 seconds. Thereafter the wort is cooled immediatelyin a stage 18. Additional hop substances or aromas may be injected intothe pasteurized and cooled clear wort as it flows through a stage 19 ofthe process (arrow 20). The quantity of said additions is less than 10%of the total volume. In a succeeding stage 21 of the process the wortconcentrate is filled at a controlled rate and under sterile conditionsinto supply containers, particularly into containers in which a stableouter vessel contains a sheet liner which collapses as the container isemptied. In such containers the wort concentrate may be stored and/ortransported to the consumers and can be used there, e.g., in dispensersas shown in FIG. 2.

A dispenser as shown in FIG. 2 has, e.g., a box 22, which is providedwith plug couplings 23, 24, 25 or other couplings for connection to anelectric lead 26, a water line 27 and a line 28, which leads to a supplyof CO₂. A supply tank 29 having a downwardly facing discharge opening isadapted to be replaceably inserted into the box 22. That supply tankcontains the wort concentrate. A connection to a line 31 is made by asterile coupling 30. The line 31 leads to a metering pump, e.g., adiaphragm pump 32, which is pneumatically operated and for this purposeis connected to the CO₂ -line 33, which extends inside the box 22.

A water line 34 is connected to the coupling 24 and extends through aprocessing plant 35, which contains filters, desalting means etc. Thewater line 34 leads to a metering pump 36 unless a constant waterpressure is ensured and otherwise extends into the mixing chamber of acarbonizer 37, in which the CO₂ line 33 opens too. The pump 36 may beassociated with an electric motor, which is controlled by a switchingunit 38. The switching unit 38 controls also the motor 39 for arefrigerating compressor, which supplies refrigerant to a cooling jacket40 of the carbonizer 37. In the carbonizer 37 the water and the CO₂ aremixed to produce carbonated water, which is supplied through a line 41to a mixer 42, which is also connected to the metering pump 32 by a line43. In the mixer 42 the carbonated water and the wort concentrate aremixed in a controlled ratio. The finished beverage is conducted in aline 44 to cooling coils 45, which surround the cooling jacket 40 andeffect an aftercooling and stilling and is finally conducted to anoutlet 46, which is preceded by a tap 47.

In the embodiment shown in FIG. 2, an opening of the tap 47 will causeadditional beverage to flow to the outlet 46. The pressure in thecarbonizer 37 is reduced at the same time. Follow-up CO₂ gas actuatesthe metering pump 32, which now supplies the mixer 42 with wortconcentrate at a predetermined ratio to the CO₂ gas. The supply of wateris controlled by the control device 38 and the pump 36. Therefrigerating means 38, 40 may be used to produce a supply of ice in thecarbonizer 37 so that a buffer operation involving a dispensing of largequantities during rush hours can be performed even though the totalrefrigerating capacity is relatively low.

Example

In the process stage 1, 100 kg malt extract are diluted with 196 kg H₂ Oand are heated to 75° C. in conjunction with an addition of 5 kgcalcined alumina. The protein coagulates owing to the temperature riseand is separated in a separator, which may consist of a centrifuge ormay contain filter cloths, together with the calcined alumina, whichconstitutes the precipitant.

The thus prepurified malt extract is allowed to stand in the decantingstage 5 for two hours and is then decanted from the dregs. In dependenceon the desired taste, 0.7 to 3 kg hop concentrate and subsequently 1.5kg special yeast are added in the process stage 7.

After the addition of hops and yeast the clear liquor is left in theprocess stage at 30° C. for 24 hours so that an alcohol content of 2.5%by volume is obtained.

In the process stage 12, additional nutrients and aromas, e.g., 100 gcitric acid to provide a tart taste, are added. In a succeeding processtage 14 the fermentation is interrupted by a shock cooling to thefreezing point and a filtration over kieselguhr succeeds the processstage 15. The flowing clear wort is pasteurized by being heating to 95°C. for 30 seconds and is subsequently cooled in stage 18. Additional hopsubstances and aromas can be added in process stage 19, virtually inone-half of the quantity in which they have been added in process stage12. The wort concentrate is subsequently filled in a cold state into thepackaging containers, which preferably have a capacity of 10 kg.

I claim:
 1. A process of producing a wort concentrate having a longshelf life, which comprises the steps of(a) diluting a malt extractcontaining protein to 30 to 40 Brix, (b) heating the diluted maltextract above the coagulation temperature of protein until the proteinhas been coagulated, (c) adding a precipitant for the protein, (d)removing the precipitated protein and the precipitant to purify the maltextract, to obtain a clear liquor (e) adding a hop concentrateand yeastto the clear liquor, and (f) fermenting the clear malt extract liquor ata temperature of 28° C. and 32° C. to obtain a wort concentrate havingan alcohol content not exceeding about 2.5%, by volume.
 2. The processof claim 1, wherein the malt extract is diluted to 35 Brix.
 3. Theprocess of claim 1, wherein the coagulation temperature is about 75° C.4. The process of claim 1, wherein the precipitant is calcined alumina.5. The process of claim 1, comprising the further step of addingnutrients and aromas to the clear liquor.
 6. The process of claim 1,comprising the further steps of interrupting the fermentation by shockcooling, filtering the cooled wort concentrate to obtain a clear wortconcentrate, and pasteurizing the clear wort concentrate.
 7. The processof claim 6, comprising the further step of adding hop aromas to thepasteurized clear wort concentrate.
 8. A process of producing acarbonated hop-malt beverage from a wort concentrate having a long shelflife, which comprises the steps of(a) diluting a malt extract containingprotein to 30 to 40 Brix, (b) heating the diluted malt extract above thecoagulation temperature of protein until the protein has beencoagulated, (c) adding a precipitant for the protein, (d) removing theprecipitate protein and the precipitant to purify the malt extract, andto obtain a clear liquor (e) adding hop concentrate and yeast to theclear liquor, and (f) fermenting the clear malt extract liquor at atemperature of 28° C. and 32° C. to obtain a wort concentrate having analcohol content not exceeding about 2.5%, by volume, and (g) dilutingthe wort concentrate at a controlled rate with CO₂ -containing water toobtain the hop-malt beverage.
 9. The process of claim 8, wherein therate of wort concentrate to CO₂ -containing water is from 1:9 to 1:10.10. The process of claim 8, comprising the further steps of cooling thehop-malt beverage and dispensing the cooled beverage undersuperatmospheric pressure.